Cleaning composition and method of cleaning internal combustion engines



Patented Apr. 2, 1940 UNITED STATES PATENT OFFICE CLEANING COMPOSITIONAND METHOD OF CLEANING INTERNAL COIWBUSTION EN- GINES No Drawing.

Application November 20, 1934 Serial No. 753,898

2 Claims.

This invention relates to cleaning compositions or compounds and moreparticularly to a cleaning composition or compound for removingdeleterious bodies that are formed in internal com- 5 bustion engines.

In the normal course of internal combustion engine operation it is wellknown and recognized that some ingredients of the crankcase lubricantcombine with oxygen to form resinous or asphal- 1 tic material commonlycalled sludge." This sludge, either alone or as a water emulsion, tendsto adhere to the motor parts and is in some ways detrimental to smoothengine performance. In some instances, emulsified sludge has been knownto completely stop the flow of oil through engine oiling systems,resulting in a rise in bearing temperatures, high enough to melt thebearing metal. To remove sludge, the engine has to be dismantled andcleaned, or washed with some suitable solvent oil. In the latter course,the solvent usually consists of ordinary petroleum fractions or the morearomatic coal tar naphthas, either alone or in mixtures of lightlubricating oil.

An object of this invention is to provide an improved cleaningcomposition for substantially dissolving the resinous and asphalticmaterial formed by the combination of oxygen with some ingredients of alubricating oil while being used in an internal combustion engine.

This and other objects and advantages will be obvious from the followingdescription. I

The general method used in cleaning internal combustion engines is todrain the used oil out of the crankcase, preferably while the engine ishot, add the solvent oil, run the engine for several minutes and drain.This procedure usually must be repeated several times if it is desiredto have the draining come out clear. The crankcase is then refilled withclean lubricating oil.

40 According to this invention, destructively hydrogenated solventnaphthas of the type usually designated hydroformed naphthas are foundto be decidedly effective solvents for resinous or asphaltic materialsformed in crankcases of internal combustion engines, and in this respectprovide an improved cleaner over the usual run of solvents such ascommon petroleum type solvents and coal tar solvents such as benzol andtoluol. The manufacture of these solvents is according to a knownprocess, but it may be gento be better solvents for the resinous andasoxides and sulphides of metals of the VI group of the periodic tableare of particularimportance, and especially mixtures thereof with oxidesof the 15 metals of the III and IV groups, and with zinc oxide, magnesiaand the like. The rate of flow may be from 1.5 to 4 volumes of oil perhour per volume of catalyst and the amount of hydrogen is ordinarilyfrom 1000 to 4000 cu. ft. per barrel 20 of oil. The physical propertiesof hydroformed solvents may be illustrated as follows:

Kauri butanol value Flash Fraction No. a

Point 25 Gravity A. P. I.

Hereafter in the specification and claims the hydroformed solventnaphthas will be known as hydrosolvents. The hydrosolvents having aboiling range of 419 F. to 460 F. have been found phaltic bodies foundin internal combustion engines. The hydrosolvent fractions may be usedas such or in a mixture consisting of the hydrosolvent fraction andother solvent oil, such as a mineral, animal or vegetable oil,preferably a higher boiling lubricating oil.

The inherent property of hydrosolvents, especially the 419 to 460- F.fraction, that makes them especially adapted for removing sludge formedin internal combustion engines may be known from the followingillustration:

.Sludge, formed by the combination of oxygen with some ingredients of alubricating oil, was separated from the lubricating oil by settling andf decantation. The action of various solvents on this separated sludgewas determined and the following results were obtained:

Percent of lubricating oil sludge soluble in solvent Solvent Kahlbaumbenzine (122 F. to 266 F. boiling range).

gleaners naphtha (300 F. to 410 F. boiling range) Toluol Hydrosolvent(365 F. to 419 F.boiling range) .7

Hydrosolvent (419 F. to 460 F. boiling range) and various changes andalternative arrangements may be made within the scope of the appendedclaims in which it is our intention to claim .all inherent novelty inthe invention as broadly as the prior art permits.

We claim:

1. A cleaning composition as cleaning agent for crankcases of internalcombustion engines containing a destructively hydrogenated solventmineral oil having a boiling range of 419 to 460 F. and a kauri butanolvalue of about 85.7.

2. A method of cleaning crankcases of internal combustion engines whichcomprises draining the used oil out of the crankcase, adding a cleaningcomposition containing a destructively hydrogenated solvent mineral oilhaving a boiling range of 419 to 460 F. and a kauri butanol value ofabout 85.7 and a mineral lubricating oil, running the engine for severalminutes and draining.

WILLIAM J. SWEENEY. JOSHUA A. TILTON.

